The present invention relates to an opening/closing structure for a housing consisting of a cover and a case and, more particularly, to an opening/closing structure for the housing of a communications equipment mounted at the elevated spot of, e.g., a pylon or a utility pole.
In general, a housing mounted at an elevated spot requires an opening/closing structure having excellent workability and operating efficiency. FIG. 5 shows a conventional opening/closing structure for a housing. Referring to FIG. 5, reference numeral 20 denotes a box-shaped case having screw holes 20a formed at the four corners of its opening portion which is open upward; and 21, a cover for closing the opening portion of the case 20. Screw insertion holes 21a corresponding to the screw holes 20a are formed in the four corners of the cover 21. In this arrangement, the cover 21 is opened or closed by threadably engaging or disengaging screws 22 inserted in the screw insertion holes 21a in or from the screw holes 20a.
In this arrangement, however, since the cover 21 is opened and removed from the case 20, if the housing is mounted at an elevated spot where a place to set aside the cover 21 cannot be assured, the opening/closing operation of the cover 21 is hindered.
In order to solve this problem, an opening/closing structure for a housing as shown in FIG. 6 is proposed. This opening/closing structure will be described with reference to FIG. 6. Reference numeral 2 denotes a case having the same shape as that of FIG. 5. A pair of brackets 3 each formed with a screw hole 3a are integrally formed on the upper portions of one side surface of the case 2. Two pairs of opposing hinge members 4 and 5 are integrally formed on the upper outer portions of the opposite side surface of the case 2. Through holes 4a and 5a are formed respectively in each pair of hinge members 4 and 5. Reference numeral 7 denotes a cover formed into a flat plate. A pair of brackets 8 each having a screw insertion hole 8a are integrally formed on one end face of the cover 7 to correspond to the brackets 3. Two brackets 30 each having a screw insertion hole 30a are integrally formed on the opposite end face of the cover 7 to correspond to the hinge members 4 and 5. Reference numerals 14 denote support shafts each horizontally fitted and inserted in the through holes 4a and 5a of each of the hinge members 4 and 5. A screw hole 14a is formed at the axial center of the outer surface of each support shaft 14.
In this arrangement, when the cover 7 is to be attached to the case 2, the cover 7 is placed on the case 2 such that its brackets 8 overlap the brackets 3 of the case 2 and that its two brackets 30 overlap the hinge members 4 and 5. Subsequently, screws 15 are inserted in the screw insertion holes 8a of the brackets 8 and threadably engaged in the screw holes 3a of the brackets 3 of the case 2, thereby fixing the brackets 8 of the cover 7 to the brackets 3 of the case 2. Then, screws 16 are inserted in the screw insertion holes 30a of the brackets 30 and threadably engaged in the screw holes 14a of the support shafts 14 that have been fitted and inserted in the through holes 4a and 5a of the hinge members 4 and 5 in advance, thereby attaching the cover 7 to the case 2. The cover 7 attached in this manner can be opened from the case 2 about the support shafts 14 as the pivot center by removing the screws 15 from the screw holes 3a of the brackets 3 of the case 2. Accordingly, even if the housing is mounted at an elevated spot where a place to set aside the cover 7 cannot be assured, the opening/closing operation of the cover 7 is not hindered.
If, however, the housing is mounted at an elevated spot, the operation must sometimes be performed at a narrow place that does not even allow the cover 7 to be opened upward. In this case, the cover 7 must be completely removed from the case 2 without opening the cover 7. When the cover 7 itself is to be replaced, it must be removed from the case 2. In this case, the brackets 3 and 8 are detached and the screws 16 are disengaged and removed from the screw holes 14a of the support shafts 14, so that the entire cover 7 is removed from the case 2. At this time, since the support shafts 14 from which the screws 16 are removed are locked by nothing, they might undesirably come out and drop from the through holes 4a and 5a. To prevent this, the support shafts 14 must be extracted. The operation of extracting the support shafts 14 requires the greatest care since the support shafts 14 are thin and short in the axial direction. Thus, a cumbersome operation is needed that takes a long period of time.